Thermometer



Nov. 10, 1936. A. s. ROBINSON THERMOMETER Filed Aug. 30, 1934 2 Sheets-Sheet 1 INVENTOR M 535mm,,

Nov. 10, 1936. A. s. ROBINSON THERMOMETER Filed Aug. 30, 1934 2 Sheets-Sheet 2 Patented Nov. 10, 1936 UNITED STA ES THERMOMETER Arthur S. Robinson, Rochester, N. Y., assignor to Rochester Manufacturing (30., Inc., Rochester, N. Y., a corporation of New York Application August 30, 1934, Serial No. 742,129

2 Claims. (01. 73-118) This invention relates to thermometers or temperature indicating devices.

An object of the invention is the provision of an improved temperature indicating device, of

neat, attractive, and novel appearance.

Another object is the provision of such a device which is illuminated so that it may be read either by night or by day.

' Still another object is the provision of such a device so designed and constructed that it may be made relatively inexpensively and so that its operating cost or upkeep is small.

A further object is the provision of an advertising novelty which will be of value in attracting attention to the advertisement dis played thereon.

To these and other ends the invention resides in certain improvements and combinationsof parts, all as will be hereinafter more fully described, the novel features being pointed out in the claims at the end of the specification.

In the drawings:

Fig. 1 is a front view of a device constructed in accordance with a preferred embodiment of the invention;

Fig. 2 is an edge view thereof;

Fig. -3 is a vertical section therethrough, substantially on the line 33 of Fig. 1;

Fig. 4 is a front view of the device with the front wall and other parts removed to show the interior construction;

Fig. 5 is a vertical section substantially on the line 55 of Fig. '7; 4'

Fig. 6 is a view substantially on the line 6-6 of Fig. '7;

Fig. 7 is a central vertical section through part of the mechanism;

Fig. '8 is a face view of an alternative form of shutter or screen disk;

Fig. 9 is a face view of another alternative form of shutter or screen disk, and

Fig. 10 is a diagrammatic view of a slightly different form of thermometer.

The same reference numerals throughout the several views indicate the same parts.

Referring now tothe preferred form of the invention illustrated in Figs. 1 to '7 inclusive, there is shown a suitable casing including, for example, a bottom wall ll, a back wall I2, end walls l3, and a front wall formed partly of a sheet metal plate I4 and partly of a glass plate IS. A top wall I6 may also be provided.

Within the casing, and'behind the part l5 of the front wall thereof, is any suitable support,

such as the partition [8, for holding suitable illuminating means preferably in the form of a light emitting tube 20 (such as the well known neon tube, or the like) which, as shown, is preferably in the shape of an arc of a circle.

Suitable graduated scale means is provided on the portion l5 of the front wall of the device. In the embodiment here shown, the graduated scale means is arranged in three lines, a middle line 25 of scale markings or graduations, an upper line 26 of identifying numerals associated with the scale markings, and a lower line 21 of identifying. numerals also associated with the scale markings. These three lines are preferably of concentric arcuate form corresponding generally to the curvature of the tube 20, and

one or another of the lines is preferably sub stantially alined with the tube. For example, the middle line of graduations 25 may be in alinement with the tube 20, and reflectors may be provided, such as the reflector 28 (Fig. 3) of frusto-conical form concentric with and above the tube 20, and the reflector 29 of frustoconical form concentric with and below the tube 20, for reflecting light fromthe tube to the upper and lower lines of the graduations 25 and 21, respectively.

The graduations themselves may be of any suitable form or kind, contrasting with the background on which they are placed. Preferably either the graduations or their background are of light transmitting character. For example, the graduations may be opaque and the background transparent, or the graduations may be transparent and the background opaque. It is usually preferred, however, to have the graduations (both the scale'markings 25 and the numerals 26 and 21) transparent,-or at least light transmitting, and to have 'the background opaque. This may'be accomplished, for example, by covering the major portion of the glass plate l5 with black paintor any other suitable opaque substance, ,leaving the graduations uncovered. so that they will form transparent or translucent portions of an otherwise opaque or materially less transparent wall.

Within the casing is a suitable support, such as the bracket or standard 35, in which is-rotatably mounted a shaft 38' concentric with the arcs of the tube 20 and the graduations 25 26, and 21.

This shaft is suitably connected tofone end of a temperature responsive device, such as the coiled bi-metallic thermostatic element 31, the

other end of which is suitably held in fixed position as by being inserted between two fixed pins 38 on the standard 35. As the temperature rises or falls, the temperature responsive device 31 will, in known manner, change its shape, which will cause rotation of the shaft 36 in one direction or the other.

The shaft 36 is also provided with a hub or boss 40 pinned -or otherwise securely fixed to the shaft, on which a shutter disk or screen member 4| is mounted and against which it may be securely clamped by means of a member 42 held in place by a screw 43. By loosening the screw 43, the disk 4| can be turned with reference to the shaft 36, for purposes of adjustment and calibration. For the purpose of aiding in such adjustment, one of the members 40 or 42 is provided with a pin 44 projecting into a hole in the other member, to prevent relative rotation of the members 40 and 42 even when-the screw 43 is loosened. Thus by loosening the screw 43, the disk 4| is loosened so that its positionmay be shifted, but by grasping the member 42 which is conveniently accessible at the front of the disk 4|, one may easily hold the parts 42, 46, and 36 against rotation and thus bring the disk 4| into exactly the position desired with reference to the shaft 36, after which the screw 43 may be again tightened.

The shutter or screen disk 4| has different portions on its periphery of different diameters, as plainly shown in Figs. 1 and 4. The portion of smaller diameter is of slightly less diameter than the innermost line of graduations 21, while the portion of larger diameter is of a diameter to overlap one or more of the lines of graduations, and there is an abrupt radial step between the two portions, as shown. The disk lies preferably on the rear side of the wall carrying the graduations, so that it will intercept part of .the light from the tube 20 which would otherwise reach the graduations. of the disk of smaller diameter acts as a counterweight to counterbalance the extra weight of the part of the disk of larger diameter, so that gravity will not tend to turn the disk in either direction.

In the form shown in Figs. 1 and 4, the larger diameter part of the shutter disk overlaps the middle line 25 of graduations and the lower line 21, but not the upper or outer line 26. Thus, when the device is in operation, light will shine at all times through the transparent or translucent graduations 26, but light will shine through the other graduations 25 and 21 only to the extent permitted by the position to which the disk 4| is rotated. The disk is so set on its shaft 36, of course, that the dividing line between the smaller diameter part of the disk and the larger diameter part of the disk corresponds at all times to the temperature. As the temperature rises, the thermostatic element 31 turns the shaft 36 and the disk 4| in a clockwise direction when viewed as in Figs. 1 and 4, so that a greater portion of the graduations 25, become unmasked and visible, and a higher indication of temperature is seen by an observer. When the temperature falls, the thermostatic element 31 turns the shaft 36 and disk 4| in a counterclockwise direction, so that less of the graduations 25 are visible and a lower temperature indication is given to the observer. The spacing of the various graduations is, of course, properly calibrated with the physical characteristics of the thermostatic element 31, so that the device indicates temperature accurately in degrees at all times.

A flange 48 on the part tions visible at all times and the inner and middle lines obscured in part by the shutter disk, it is possible to construct the disk in various other ways. For example, as shown in Fig. 8, the disk 50 has a portion 5| in alinement with the middle line 25 of graduations, and has openings 52 through which light may shine at all times onto the inner line 21 of graduations, and light may at all times shine also on the outer line 26 of graduations without interference from the shutter 50. When a shutter of this form is used, both the inner and outer lines 26 and 21 are visible at all times, and the temperature is read by noting the point at which the illumination of the graduations 25 ceases.

Again, as in Fig. 9, the shutter 55 may be constructed so that its part of larger diameter overlies all three of. the lines of graduations indicated diagrammatically at 26a, 25a, and 21a in this figure. Thus, all three lines of graduations will be dark or obscured in positions higher than the indicated temperature, while all three lines will attention. The continuous band of light (usually a brightly colored light) visible from the lowest graduation up to the temperature to be indicated, is-unusual and pleasing, sothat passers-by will stop to look at it. Other features may be added, however, to make the device still more of an advertising novelty.' For example, another light emitting tube 60 (such as a neon tube, or the like) may be'placed on the front of the lower part H of the frontwall of the casing and formed into a rectangular outline or any other suitable shape. Advertising matter of any desired kind may be placed within the outline of the tube 60, to be illuminated by the light from the tube and to have attention directed thereto by the tube. If desired, the light emitted by the tube 60 may be of a different color from that emitted by the tube 20, one being, for example, a green tube, and the other being, for example, a red or orange tube.

Electric current is supplied to the device for lighting the tubes, through any suitable extension cord or lead-in wire 65, which is connected to a transformer 66 having leads 61 leading to the tube 20, and current may also be supplied to another transformer 68 having leads 69 leading to the tube 60.

The casing itself may be provided with suitable vent holes or openings and 1| (Fig. 2) so that air may pass freely into and out of the casing in order to keep the interior of the casing at the same temperature as the exterior air, the temperature of which is to be indicated. If preferred, the device may be made so that the temperature responsive element 31 is outside of the casing itself.

While the preferred form of construction, as above described, embodies a rotatable shutter or screen disk and an arcuate illuminating tube, it is not necessary that the parts be of this form. For example, as shown diagrammatically in Fig. III, a straight neon tube 15, arranged vertically or otherwise, may be provided, in front of which is placed a plate 16 having the desired graduated scale thereon. Between the tube and the plate 16in a shutter or screen member 11 operatively connected at 18 to an arm 19 which is counterweight 82 on the opposite side of the pivot from the shutter 11. The position of this arm is controlled by a heat responsive device 83 which may be similar to or substantially identical with the thermostatic element 31 previously described. As the temperature rises and falls, the heat responsive element 83 will cause the arm 19 to move up and down, which will cause corresponding movement of the shutter 11, which, in turn, will intercept more or less of the light which would otherwise shine from the tube I upon the graduated scale means indicated diagrammatically at 16.

The shutter 'll should, of course, be wide enough so that asthe arm 19 swings up and down, the resulting sidewise displacement of the shutter will not cause it to expose some of the graduations which should not be exposed. Or, instead of making the shutter 11 relatively wide, it can be held against lateral movement by suitable guides and connected to the arm 19 by a pin and slot connection.

In both forms of the invention, it is seen that the illuminating means provides a continuous band or streak of light, and that the disk or screen, placed between this continuous streak of light and the eye of the observer, intercepts more or less of the light, depending on the temperature, and thus indicates to the observer, by the position of the end of the visible streak of light, the temperature which is influencing the thermostatic element.

While certain embodiments have been disclosed, it is to be understood that the inventive idea may be carried out in a number of ways. This application is therefore not to be limited to the precise details described, but is intended to cover all variations and modifications thereof falling within the spirit of the invention or the scope of the appended claims.

I claim:

1. Temperature indicating means comprising a light emitting tube, an arm pivotally mounted for partial rotation, temperature responsive means for moving said arm, and screen means carried by and movable with said arm, said screen means having a portion substantially in alinement with said tube to obscure a portion of the length of said tube variable in accordance with movement imparted to said screen means, while leaving light from another variable length of said tube visible.

2. Means for indicating a variable quantity, comprising a light emitting tube providing a substantially continuous band of light, opaque shielding means movable in response to variations in the quantity to be indicated, for masking a variable part of said band of light while leaving visible a length thereof variable in accordance with said variable quantity, and graduated scale means associated with said band of light so that the variable visible length of said band of light may be readily observed in conjunction with said scale means.

ARTHUR S. ROBINSON. 

